Reefing ships  sails



'UNITED STATES PATENT OFFICE.,

JAMES EMERSON, OI" VORCESTER, MASSACHUSETTS.

REEFING- SHIPS SAILS.

Specification of Letters Patent No. 17,031, dated April 14, 1857'.

To all whom it may concern Be it known that I, JAMES EMERSON, ofINforcester, in the county of Vorcester and State of Massachusetts, haveinvented new and useful Improvements in Reeng Ships Sails; and I dohereby declare that the fol lowing is a full and exact description ofthe same.

My inproyement relates to that class of reeling sails where an eXtrayard is used, the reetng being effected by chains or ropes leading downto the deck of the vesel, so that the sails can be reefed while the menare on deck.

To enable others skilled in the art to make and use my invention, I willproceed to describe it, and by referring to the annexed drawings, makinga part of this specification it will be readily understood.

Figure l represents the ordinary top-sail yard, with the roller O,attached by the bands K and clamps D. This roller is turned by the gearsC at each end, which gears `are operated by the pinions J. On each endof this roller there is a screw E, these screws are right and lefthanded as shown, and the pitch of the thread is equal to the increase ofthe sail in width, so that the leach of the sail will follow the screw,and is kept in place by the claws X, which are under the screws as shownby Fig.y 2. The leach or roper on the edge of the sail runs throughthese claws. The claws are secured to a nut on the screws and are keptsteady by the end of the nut sliding in a slot in the end of the yard.Pinions J are attached to the arbors A which are operated by the endlesschain Y passing around the pulleys R, this chain also passes around thepulley L in the middle of the yard. To this pulley is also attachedanother endless chain running down by the mast to the deck. Pawls P actin the ratchet I and hold the roller as the sail is rolled up. Ifnecessary the arbors A can be turned by the same cranks or wrenches withwhich the screws B are turned. Clamps D are made as shown in Fig. 3, sothat they will close on to the bare roller or can be increased in sizeso that the sail can be rolled inside of them.

To reef the sail, one man goes aloft and unscrews the clamps D, then byhauling the endless chain that leads down by the mast on deck the rollerO will roll the sail up as fast as the yard is lowered by the halyards.Then the sail is rolled up screw the clamps D tightly to the sail on theroller.y Then wishing to unroll the sail one man go aloft, unscrew theclamps D, lift the pawls P out of the ratchets, then hoist away, but theroller should not be allowed to unroll any faster than the yard ishoisted.

What I claim is- The adjustable clamps D, when arranged so as to beenlarged or decreased as required, secondly I claim the screws E andclaws X on the roller C) for spreading the sail.

JAMES EMERSON. Witnesses:

JESSE W. GooDRIcH, Jol-1N J. ONmt.

